#ifndef VarKamSpring_H
#define VarKamSpring_H

/* Last edited on DATE TIME by USER */

#include <Energy.h>

typedef struct VarKamSpring_data_t 
{
  double length;   /* desirable length of a single @{edge->?} in the display plane */
  double strength; /* a constant */
} VarKamSpring_data_t;

Energy_t VarKamSpring_new(void);
  /* In Kamada's energy, a spring is attached between every @place of
    triangulation nodes u, v, adjacent or not, whose length is
    equal to the graph-theoretical distance between u and v in T.
    
    In this version, the distances are computed by setting each @{edge->?}'s
    length to {length * sqrt (Na/Nb + Nb/Na)} where {Na} and {Nb} are
    the endpoint degrees. */
  
#endif